"Classroom data are like teddy bears and real data are like a grizzley bear with salmon blood dripping out its mouth."
Jenny Bryan                  Â
"Up to 80% of data analysis is spent on the process of cleaning and preparing data."
cf. Wickham, 2014 and Dasu & Johnson, 2003 Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
"Cannot emphasize enough how much time you save by putting analysis efforts into tidying data first."
Hilary Parker                  Â